Driving in L9 and DFM

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Jgrimberg1979

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No, I wish they did notify when it’s engaged. :)
You can’t feel it turn on it? I swear I have not only that you know if it’s in dfu, it’s when you are idiling and not giving it much throttle. That will tell you it’s shutting down half the engine technically
 

jimgeb

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It would be interesting to find out if the lifters fail as much even if AFM/DFM is deleted.
 

SCiesie154

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Does anyone know what the maximum speed would be in L9? Here in the free state of South Dakota we have 80mph speed limits.
 

SCiesie154

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Thanks olyeir, I didn't know we had a speed limiter. That is kinda like Close Up toothpaste, "It takes the worry out of being close." (-:
 

CMoore711

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It would be interesting to find out if the lifters fail as much even if AFM/DFM is deleted.

I realize my rig is the previous gen ‘15 Yukon Denali XL; I have the 6.2 L86 and 8l90e 8 speed.

But in regards to your comment here.

I purchased my vehicle CPO with 22K miles. Installed a Range AFM disable device at about 30K miles. At 78K miles I still had a lifter failure. Covered under the power train warranty at the time.

There is also a difference between disabling the AFM/DFM and deleting it.

Disabling AFM/DFM is something done simply with a tune or Range type device. Still maintaining the stock mechanicals just not allowing the AFM/DFM to function or engage.

Deleting AFM/DFM is more of a mechanical delete of the entire system and parts; Changing the lifters, cam, VLOM, and some other engine parts (still researching the parts list) to a standard or more “traditional” push-rod V8. Think GM LS# motors. Some owners who have gone down this path have also reported a slight 1-3 increase in mpg. Perplexed.
 

Geotrash

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I realize my rig is the previous gen ‘15 Yukon Denali XL; I have the 6.2 L86 and 8l90e 8 speed.

But in regards to your comment here.

I purchased my vehicle CPO with 22K miles. Installed a Range AFM disable device at about 30K miles. At 78K miles I still had a lifter failure. Covered under the power train warranty at the time.

There is also a difference between disabling the AFM/DFM and deleting it.

Disabling AFM/DFM is something done simply with a tune or Range type device. Still maintaining the stock mechanicals just not allowing the AFM/DFM to function or engage.

Deleting AFM/DFM is more of a mechanical delete of the entire system and parts; Changing the lifters, cam, VLOM, and some other engine parts (still researching the parts list) to a standard or more “traditional” push-rod V8. Think GM LS# motors. Some owners who have gone down this path have also reported a slight 1-3 increase in mpg. Perplexed.
Agree on all points. I did a full mechanical delete on my 2012 and it’s been wonderful. Yet, I also know that a lifter failure is still possible. It’s statistically less likely now, but non-AFM lifters still fail from debris, worn lifter trays, poor maintenance, and just poor metallurgy or QC during manufacture.

At some point, I will invest in a newer XL Denali I’m sure… one that’s 6 years old or so with around 100K, and it will be cheap relative to a new one. When I do, I will delete the DFM mechanically myself because I have the process down pat, and take the opportunity to refresh everything under the hood while I’m there. For $2-3K in parts and a couple of weekends, I’ll have a rig ready to roll for another 10 years. These are STILL the best, most versatile SUV you can buy, hands down. I’ll always have one.
 

jimgeb

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I realize my rig is the previous gen ‘15 Yukon Denali XL; I have the 6.2 L86 and 8l90e 8 speed.

But in regards to your comment here.

I purchased my vehicle CPO with 22K miles. Installed a Range AFM disable device at about 30K miles. At 78K miles I still had a lifter failure. Covered under the power train warranty at the time.

There is also a difference between disabling the AFM/DFM and deleting it.

Disabling AFM/DFM is something done simply with a tune or Range type device. Still maintaining the stock mechanicals just not allowing the AFM/DFM to function or engage.

Deleting AFM/DFM is more of a mechanical delete of the entire system and parts; Changing the lifters, cam, VLOM, and some other engine parts (still researching the parts list) to a standard or more “traditional” push-rod V8. Think GM LS# motors. Some owners who have gone down this path have also reported a slight 1-3 increase in mpg. Perplexed.
 

Fast_AT4

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This L9 topic is all new to me. I get in and hit D and drive away....am I missing some "performance mode" here by using "D"? Is this like a hidden "M Mode" that I have been accustom to in my previous BMW M5's? Any known downfalls to driving in L9...lifter issue specifically?
 

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